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Odds maths

Implied probability calculator.

Convert decimal odds into implied probability and compare that percentage with a simple market overround view.

Implied probability
23.81%
Decimal from probability
4.20
Market book
98.54%
Normalised share
24.16%

Decimal odds to probability

Decimal odds imply a probability of 1 divided by the odds. For example, $4.00 represents 25.00% before market margin.

Market overround

Adding each runner's implied probability shows the book percentage. A total above 100% reflects market margin or incomplete pricing.

Normalised share

Normalising adjusts one runner's implied probability by the total market book, which can make crowded markets easier to compare.

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